package com.small.common.util.val.captcha;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;

/**
 * 作者: fenny
 * 邮箱: 893146555@qq.com
 * 时间: 2017/10/17 15:04
 * 描述: png格式验证码
 */
public class CaptchaPng extends Captcha {

    private static Logger LOGGER = LoggerFactory.getLogger(CaptchaPng.class);

    public CaptchaPng() {
    }

    public CaptchaPng(int width, int height) {
        this.width = width;
        this.height = height;
    }

    public CaptchaPng(int width, int height, int len) {
        this(width, height);
        this.len = len;
    }

    public CaptchaPng(int width, int height, int len, Font font) {
        this(width, height, len);
        this.font = font;
    }

    /**
     * 生成验证码
     */
    @Override
    public void out(OutputStream out) {
        graphicsImage(alphas(), out);
    }

    /**
     * 画随机码图
     *
     * @param strs 文本
     * @param out  输出流
     */
    private void graphicsImage(char[] strs, OutputStream out) {
        try {
            BufferedImage bi = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
            Graphics2D g = (Graphics2D) bi.getGraphics();
            AlphaComposite ac3;
            Color color;
            int len = strs.length;
            g.setColor(Color.WHITE);
            g.fillRect(0, 0, width, height);
            // 随机画干扰的蛋蛋
            for (int i = 0; i < 15; i++) {
                color = color(150, 250);
                g.setColor(color);
                // 画蛋蛋，有蛋的生活才精彩
                g.drawOval(num(width), num(height), 5 + num(10), 5 + num(10));
                color = null;
            }
            g.setFont(font);
            int h = height - ((height - font.getSize()) >> 1),
                    w = width / len,
                    size = w - font.getSize() + 1;
            /* 画字符串 */
            for (int i = 0; i < len; i++) {
                // 指定透明度
                ac3 = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.7f);
                g.setComposite(ac3);
                // 对每个字符都用随机颜色
                color = new Color(20 + num(110), 20 + num(110), 20 + num(110));
                g.setColor(color);
                g.drawString(strs[i] + "", (width - (len - i) * w) + size, h - 4);
                color = null;
                ac3 = null;
            }
            ImageIO.write(bi, "png", out);
            out.flush();
        } catch (IOException e) {
            LOGGER.error("生成PNG图形码异常", e);
        } finally {
            try {
                if (out != null) {
                    out.close();
                }
            } catch (IOException ignored) {
            }
        }
    }
}